fw/icE1usb: Reorganize fields in misc peripheral

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
diff --git a/firmware/ice40-riscv/icE1usb/misc.c b/firmware/ice40-riscv/icE1usb/misc.c
index 6f40fd4..a8e48b3 100644
--- a/firmware/ice40-riscv/icE1usb/misc.c
+++ b/firmware/ice40-riscv/icE1usb/misc.c
@@ -21,8 +21,10 @@
 		uint16_t rx;
 		uint16_t tx;
 	} e1_tick[2];
-	uint32_t gps;
-	uint32_t time;
+	struct {
+		uint32_t pps;
+		uint32_t now;
+	} time;
 	uint32_t pdm[8];
 } __attribute__((packed,aligned(4)));